| Computer Code: |
NSS |
Preferred Map Code: |
notEntered |
| Status Code: |
Full |
| Age range: |
Furongian Epoch (EF)
— Tremadocian Age (OTR) |
| Lithological Description: |
Grey to white turbiditic metasandstone and interbedded blue-grey silty metamudstone. |
| Definition of Lower Boundary: |
Not known, not exposed. |
| Definition of Upper Boundary: |
Conformable contact with Holyhead Formation (HHD). |
| Thickness: |
Approx. 360 m to > 1000 m. |
| Geographical Limits: |
Holy Island; Anglesey. |
| Parent Unit: |
Holy Island Group (NHI)
|
| Previous Name(s): |
South Stack Group [Obsolete Name and Code: Use NSS]
(-2346)
|
| Alternative Name(s): |
none recorded or not applicable
|
| Stratotypes: |
| Type Area |
South Stack, Holy Island, Anglesey. |
| Reference(s): |
| Shackleton, R M, 1954. The structure and succession of Anglesey and the Lleyn Peninsula. British Association for the Advancement of Science, Vol.11, p.106-108. |
| Greenly, E. 1919. Geology of Anglesey. Memoir of the Geological Survey, UK. |
| Blake, J F. 1888. The Monian System of rocks. Quarterly Journal of the Geological Society, Vol. 44, 476-480. |
| Phillips, E. 1991. Progressive deformation of the South Stack and New Harbour Groups, Holy Island, Western Anglesey, North Wales. Quarterly Journal of the Geological Society, Vol. 148, p. 1091-1100. |
| 1:50K maps on which the lithostratigraphical unit is found, and map code used: |
| none recorded or not applicable |
